460 Short Commimkatiotis : — 



which lie just below the surface, and feed on the roots of the 

 plants. Sometimes whole patches of these and similar plants 

 have been nearly stocked up from the rockwork, or the pots 

 in which they grew. But to return to the rooks : I am sur- 

 prised to find it mentioned (p. 244. )j as a new fact in natural 

 history, that '' the husk of grain taken by the rook is sepa- 

 rated, in the rook's stomach, from the grain itself, and is 

 afterwards discharged from the mouth of the rook in masses 

 of the size [nearly] of a pigeon's egg." This fact I have 

 repeatedly observed, and any one may satisfy himself of it, 

 who will but examine the ground under a rookery in the 

 spring, where he will find the surface strewed with abun- 

 dance of such rejectamenta.* I may here mention one cir- 

 cumstance connected with this fact, which is not noticed by 

 your correspondent : the rooks, to grind their corn, seem to 

 require stones, like other millers f; and, for this purpose, 

 they swallow lumps of brick, grit, broken platter, coal, and 

 other like substances (but chiefly brick), which are discharged 

 again along with the pellets of husks. These fragments of 

 brick, &c., are from the size of a vetch seed, or less, to that 

 of a damson stone, rough and irregular sometimes, but 

 usually more or less rounded or bouldered by the action of 

 grinding in the bird's stomach, before they are thrown up in 

 the pellets ; and the pellets, in consequence, are sometimes 

 slightly tinged with a red or brickdust colour. I herewith 



* [Mr. Hewitson, in his Sriiish Oology y t. 71., has spoken of it as a fact 

 hitherto unnoticed, except in this Magazine, VII. 244. In the case de- 

 scribed by Mr. Hewitson, " the whole surface of the ground underneath 

 the trees [which bore the rookery] was thickly strewed with disgorged 

 pellets similar to those ejected by the owl, but consisting entirely of the 

 husks of oats ; and must have contained, altogether, the remains of many 

 bushels. [We shall add his speculation on this fact.] I suspect, however, 

 that the rook is by no means so destructive from choice as one might be 

 led (from what I have stated) to infer ; and that the dryness of the spring, 

 and the consequent difficulty in obtaining its usual food, had driven it to 

 a more than usual destruction of grain. If I am right, it will also account 

 for the habit having remained unnoticed." 



Bushnan, in his Introduction to the Study of Nature y proposes, in p. 157., 

 that birds adapt the time of rearing their young to the period in which 



there will be a certainty of procuring food suitable for them " The 



rook hatches in April, when the turning up of the soil affords abundance 

 of grubs and worms, which could not be found at a later season ; and, when 

 this source fails, the common chafer affords a long supply." How long 

 was the rook in existence ere tillage was much practised '?] 



-|- Most, if not all granivorous birds, I believe, as well as some others, 

 swallow grit, in order to promote the trituration of their food. I have 

 sometimes been much amused by seeing chickens, especially such as have 

 been confined in a pen, and cannot help themselves to grit, swallow with 

 avidity large pieces of broken oyster shell, which have been given to them, 

 of the size of a sixpence, or larger. — W. T, B. 



